科学美国人60秒 科学家终于对口吃有了合理的解释（在线收听）

This is Scientific American’s 60-Second Science. I’m Karen Hopkin.

这里是科学美国人——60秒科学系列，我是凯伦·霍普金。

When you stop to think about it, it’s not all that easy to speak.

当你停下来思考时，就会发现说出话来并不那么容易。

First you have to think of something to say.

首先你得想好要说什么。

Then your brain has to tell your mouth to say it.

然后你的大脑会告诉你的嘴巴说出来。

Interruptions anywhere along this articulation pathway can impair the utterance, and create something like a stutter.

在这条发音通路上的任何地方出现中断都可能阻碍说话，并造成口吃之类的症状。

Now, studying a neurocomputational model of this complex process, researchers have found that stuttering stems from a glitch in the neural circuit that initiates speech.

现在，研究人员过研究这一复杂过程的神经计算模型，发现口吃源于开始说话的神经回路中的一个小故障。

They presented their findings at the Meeting of the Acoustical Society of America.

他们在美国声学学会会议上展示了他们的发现。

“My main research interest is translating how the brain translates thoughts...”

“我的主要研究兴趣是解释大脑是如何将思想转变为...”

Frank Guenther of Boston University.

波士顿大学的弗兰克·冈瑟说。

“... into movements of the tongue and the other speech articulators that convey these thoughts to another person.”

“...舌头上的动作，解释那些把这些想法传达给另一个人的发音器。”

He says that stuttering is very common and it happens in all languages.

他表示，口吃很常见，在所有语言中都存在这种现象。

It’s estimated that about one percent of the world’s population stutters.

据估计，世界上大约有1%的人口吃。

Despite this, and despite being studied at least as far back as the ancient Romans, our understanding of what causes stuttering has been until recent years very poor.

尽管如此，尽管研究至少可以追溯到古罗马时期，但直到最近几年，我们对口吃的原因的理解还是很贫乏。

Numerous neural circuits come into play when it comes to generating speech.

在产生话语时，许多神经回路都发挥了作用。

But the key drivers can be broken down into two main circuits.

但关键的驱动因素可以分为两个主要电路。

One is an initiation circuit and the other is an articulation circuit.

一个是启动电路，另一个是发生电路。

To understand the function of these circuits it’s useful to consider something like the energizer bunny

为了理解这些电路的功能，可以考虑一些类似劲量兔的东西

which has an on/off switch as well as a set of motors and gears that make the bunny walk and play drums when the switch is turned on.

它有一个开启/关闭开关以及一组马达和齿轮，开关打开后，兔子就会走路和打鼓。

The on/off switch initiates the movement. And the motors and gears make it happen.

开启/关闭开关启动运动。马达和齿轮使这一运动发生。

But which of these circuits can lead to a stutter?

但这些电路中哪一种会导致口吃呢?

To find out, Guenther pieced together equations that represent how the neurons that form these circuits interact.

为了找到答案，冈瑟拼凑了一些方程，这些方程代表了构成这些电路的神经元是如何相互作用的。

These equations describe neural activity in different parts of the brain including the basal ganglia, cerebellum, and the cerebral cortex.

这些方程式描述了大脑不同部位的神经活动，包括基底神经节、小脑和大脑皮层。

One set of equations represents the electrical activity of the neurons in all of these regions.

一组方程代表了所有这些区域神经元的电路活动。

Another the strength of the connections they form with each other.

另一组方程是他们彼此之间连接的力量。